1. Field of the Invention
The present invention relates to a device for the identification of metal alloys by the X-ray fluorescence method.
2. Description of the Prior Art
Many businesses manufacture products from stock pieces of metal alloys purchased from a manufacturer of such stock. If several different alloys having a similar appearance are being stored and utilized in the daily manufacturing process, a mixed material problem can occur. If the wrong alloy is utilized in the manufacture of a part, it may result in the premature failure of the part during normal use. Such a failure has the potential for serious economic consequences and physical danger.
As businesses became aware of the mixed metals problem, they turned to quantitative inspection techniques including X-ray fluorescence. Many types of devices for X-ray flourescence analysis are known. Radiation is emitted by a sealed radioactive source and impinges upon the sample being tested. The radiation initiates the emission of secondary X-radition from the sample. The secondary X-radiation is sensed and the concentration of any element in the sample is determined by the intensity of the characteristic X-rays of the element in the spectrum. Use can be made of special filters which make it possible to eliminate certain spectral lines so that only those that are typical of a given element are permitted to remain. Thus, by using a series of different filters, it is possible to determine the composition and concentration of the constituents of any sample.
U.S. Pat. No. 3,992,542 discloses an apparatus for the continuous analysis of samples. The apparatus includes a measuring head having a radioactive source and a counting assembly connected to the radiation detector. A sequential filter transfer unit has a conveyor driven in reciprocating motion between a filter stack and a gap between the source and the detector. A sample transfer unit with inclined parallel slide ramps and a receiving trough fitted with a push plate for passing the sample in front of the source in unitary sequence is controlled by a mechanical control assembly and an electronic assembly for recording signals delivered by the radiation detector after analysis of each sample. However, such a device has the disadvantage of requiring a sample to be brought to the device for analysis. Furthermore, the sample must be in a certain size range in order to be passed in front of the radioactive source.